Black Yome ni Yoroshiku!  

Regards to Black Wife!, ブラック嫁によろしく！

Shinta, a typical high school student heading to class, experiences another accident. Miraculously, instead of passing away, he is rescued by an enigmatic woman clad entirely in black. She reveals herself as a shinigami and explains that she has arrived to fulfill her vow to become Shinta's spouse.